Actually I doubt if it really bothers them, they are number one in the UK and they are a UK store. they don't really need US traffic as there prices will only be competitive in the UK.
Dp is on number one on my Google for 'Digital Point' P.S. Actually whenever I have to log in to DP i go to google, type digital point there and hit am feeling lucky. Some of you may find it wierd, but thats my way to lonin into DP. And happy to know that am not the onlyone to do so. Assassin also follows the same way (perhaps)
But when i enter Digital point and hit I'm feeling lucky it takes me to this forum not www.digital-point.co.uk :-s
Different data centers can carry slightly different results. I noticed on certain days, my webpage would index at about 3k+ pages and one time I even caught it on 5k+ pages. And now I am back down to about 3k+ pages. Don't think everytime you go into google, everybody is logging into the same place or else you would think how they can carry billions of connections each minute if they have only one datacenter to connected to. That was a bit off topic but yeah, since your search on the .co.uk then I would figure that they give more priority to sites with the .uk extension.